Join the Meeting Place for Moms!
Talk to other moms, share advice, and have fun!

(minimum 6 characters)

Which one to go by

At my last ultrasound i went in at 9 weeks according to my last period but the baby was measuring 10 weeks. This was a month ago. My question is am I now 14 weeks or am I 15 weeks. Which one do you go by

Answer Question

Asked by mycheyl at 11:06 AM on Jul. 12, 2009 in Pregnancy

Level 2 (12 Credits)
Answers (6)
  • you go by your first ultrasound, i had the same issue, only by my period I was 3 days ahead.

    Answer by ArmyWife9-2-08 at 11:14 AM on Jul. 12, 2009

  • There's always a window of 2 weeks in either direction, but I would probably go by the us

    Answer by motherofanaries at 11:19 AM on Jul. 12, 2009

  • My doctor went by my period and date of conception. I only saw SO one day that month and it was 14 days after my period. The ultrasounds all through the pregnancy were behind 7-10 days, and I made it clear to them that I could not possibly have conceived 7-10 days later because SO was out of town working, lol! Well, even my doctor said that ultrasounds can be off by 7-10 days in either direction. So, if your periods are regular and you have a good idea when you conceived, I would go by those dates. My baby was born two days before the due date based on my calculations.

    Answer by DeTora_Family at 11:32 AM on Jul. 12, 2009

  • Deff by the Ultrasound- it mesures baby by growth not your period.

    Answer by judith_visco at 11:33 AM on Jul. 12, 2009

  • You go by the ultrasound. Even if your periods are regular, you might not ovulate on the exact same day each cycle.

    With my current pregnancy, I got pregnant the day after my period stopped and I have a regular 30 cycle.

    Answer by ThrivingMom at 12:05 PM on Jul. 12, 2009

  • To make things easier on yourself. I would go by what ever the doctor goes by. He will be the one caring for you. Chances are he will not change your due date based on an ultrasound. Like everyone else has said US can be off by 7-10 days and for decades doctors have been using your period to judge you gestational age. Neither of these are absolutely accurate but to keep your self sane, synchronize you calender with the doctors.


    Answer by studentteach at 12:07 PM on Jul. 12, 2009

Join CafeMom now to contribute your answer and become part of our community. It's free and takes just a minute.